1261368851 has 2 divisors, whose sum is σ = 1261368852. Its totient is φ = 1261368850.

The previous prime is 1261368841. The next prime is 1261368853. The reversal of 1261368851 is 1588631621.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1261368851 - 2¹⁰ = 1261367827 is a prime.

It is a Sophie Germain prime.

Together with 1261368853, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1261368799 and 1261368808.

It is not a weakly prime, because it can be changed into another prime (1261368853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 630684425 + 630684426.

It is an arithmetic number, because the mean of its divisors is an integer number (630684426).

Almost surely, 2^1261368851 is an apocalyptic number.

1261368851 is a deficient number, since it is larger than the sum of its proper divisors (1).

1261368851 is an equidigital number, since it uses as much as digits as its factorization.

1261368851 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 69120, while the sum is 41.

The square root of 1261368851 is about 35515.7549687459. The cubic root of 1261368851 is about 1080.4732867892.

The spelling of 1261368851 in words is "one billion, two hundred sixty-one million, three hundred sixty-eight thousand, eight hundred fifty-one".